The present invention relates generally to closures for containers, and specifically to a tamper-evident closure having a separated break away band, and a method of manufacturing such a closure.
Various configurations of tamper-evident container closures are known in which a frangible band breaks away from the closure upon opening. The band is connected to the closure by a number of relatively thin, easily severable bridges or pads, and remains on the container finish upon the initial opening of the container.
U.S. Pat. Nos. 4,550,844 and 4,807,771 disclose closures including a large number of tabs extending upwardly and inwardly from the base of the band and abutting a large annular shoulder projection or breaker ledge on the container finish beneath the screw thread to cause separation of the tamper-evident band upon the first opening of the container. Such closures require a multi-step production system to bend the tabs into an upwardly projecting position. Also, U.S. Pat. No. 4,807,771 discloses that such closures are often unsatisfactory for use on relatively larger-mouthed containers.
Another disadvantage of conventional closures having integrally molded break away bands is that the void area between the bridges or pads must be created by molds having side-action capability or by a second cutting operation. This process increases the complexity and cost of producing such closures.
A further disadvantage of conventional tamper-evident closures having break away bands is that the break away band often fails to disengage from the closure upon the initial opening of the container. This is due to the limitations in break away band configuration imposed by integrally molding the band to the closure.
A still further disadvantage of conventional tamper-evident closures employing break away bands is that the tamper evident band is easily visible, and may restrict container styling alternatives.
Thus, an object of the present invention is to provide a tamper-evident closure in which the break away band is readily detached from the closure upon the initial opening thereof.
A further object of the present invention is to provide a method of manufacturing a tamper-evident closure in which the break away band is molded separately from the closure, and is subsequently secured to a lower edge of the closure.
A still further object of the present invention is to provide a tamper-evident closure which may be successfully employed on large-mouthed containers.